Medical instrument and method of use

ABSTRACT

An instrument for thermally-mediated therapies in targeted tissue volumes or for volumetric removal of tissue. In one embodiment, the instrument has an interior chamber that includes a diffuser structure for diffusing a biocompatible conductive fluid that is introduced under high pressure. The interior chamber further includes surfaces of opposing polarity electrodes for vaporizing the small cross-section diffused fluid flows created within a diffuser structure. In one embodiment, the diffuser structure includes a negative temperature coefficient of resistance material between the opposing polarity surfaces. The NTCR structure can self-adjust the lengths of current paths between the opposing polarities to insure complete vaporization of the volume of flow of conductive fluid. The non-ionized vapor phase media is ejected from a working surface of the instrument and a controlled vapor-to-liquid phase chance in an interface with tissue applies thermal energy substantially equal to the heat of vaporization to ablate tissue. In another embodiment, the instrument provides voltage means for converting the non-ionized vapor phase media into an ionized media or plasma for applying energy to body structure.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.11/329,381 filed Jan. 10, 2006, now U.S. Pat. No. 8,444,636, whichclaims benefit of Provisional U.S. Patent Application Ser. No.60/643,045 filed Jan. 11, 2005 titled Surgical Instrument and Method ofUse. U.S. patent application Ser. No. 11/329,381 also is acontinuation-in-part of U.S. application Ser. No. 10/681,625, filed Oct.7, 2003 titled Medical Instruments and Techniques for Thermally-MediatedTherapies now U.S. Pat. No. 7,674,259, which is acontinuation-in-part-of Ser. No. 10/017,582, filed on Dec. 7, 2001,titled Medical Instruments and Techniques for Highly LocalizedThermally-Mediated Therapies now U.S. Pat. No. 6,669,694. U.S. patentapplication Ser. No. 11/329,381 also is a continuation-in-part of U.S.application Ser. No. 11/158,930 filed Jun. 22, 2005 titled MedicalInstruments and Techniques for Treating Pulmonary Disorders now U.S.Pat. No. 7,892,229. U.S. patent application Ser. No. 11/329,381 also isa continuation-in-part of U.S. application Ser. No. 11/244,329 filedOct. 5, 2005 titled Medical Instrument and Method of Use now U.S. Pat.No. 8,016,823. Provisional U.S. Patent Application Ser. No. 60/643,045and U.S. application Ser. Nos. 10/681,625, 11/158,930, 11/244,329, and11/329,381 are incorporated herein by this reference and made a part ofthis specification, together with the specifications of all othercommonly-invented applications cited in the above applications.

FIELD OF THE INVENTION

This invention relates to surgical instruments for applying energy totissue, and more particularly relates to a system for ablating,shrinking, sealing, welding, volumetrically removing or creating lesionsin body structure or tissue by means of contacting body structure withnon-ionized vapor phase media wherein a subsequent vapor-to-liquid phasechange of the media applies thermal energy to the body structure.

BACKGROUND OF THE INVENTION

Various types of radiofrequency (Rf) and laser surgical instruments havebeen developed for delivering thermal energy to tissue, for example tocause hemostasis, to weld tissue or to ablate tissue. While such priorart forms of energy delivery work well for some applications, Rf andlaser energy typically cannot cause highly “controlled” and “localized”thermal effects that are desirable in microsurgeries or other precisionsurgeries. In general, the non-linear or non-uniform characteristics oftissue affect both laser and Rf energy distributions in tissue.

What is needed is an instrument and method that can controllably deliverthermal energy to targeted tissues to ablate, coagulate, seal, shrink,or disintegrate tissue that does not cause stray electrical current flowin tissue.

SUMMARY OF THE INVENTION

The present invention is adapted to provide improved methods ofcontrolled thermal energy delivery to localized tissue volumes, forexample for ablating, sealing, coagulating or otherwise damaging thetissue. Of particular interest, the method causes thermal effects intargeted tissue without the use of RI current flow through the patient'sbody.

In general, the thermally-mediated treatment method comprises causing avapor-to-liquid phase state change in a selected media at a targetedtissue site thereby applying thermal energy substantially equal to theheat of vaporization of the selected media to said tissue site. Thethermally-mediated therapy can be delivered to tissue by suchvapor-to-liquid phase transitions, or “internal energy” releases, aboutthe working surfaces of several types of instruments for endoluminaltreatments or for soft tissue thermotherapies. FIGS. 1A and 1Billustrate the phenomena of phase transitional releases of internalenergies. Such internal energy involves energy on the molecular andatomic scale—and in polyatomic gases is directly related tointermolecular attractive forces, as well as rotational and vibrationalkinetic energy. In other words, the method of the invention exploits thephenomenon of internal energy transitions between gaseous and liquidphases that involve very large amounts of energy compared to specificheat.

It has been found that the controlled application of internal energiesin an introduced media-tissue interaction solves many of the vexingproblems associated with energy-tissue interactions in Rf, laser andultrasound modalities. The apparatus of the invention provides afluid-carrying chamber in the interior of the device or working end. Asource provides liquid media to the interior chamber wherein energy isapplied to instantly vaporize the media. In the process of theliquid-to-vapor phase transition of a saline media in the interior ofthe working end, large amounts of energy are added to overcome thecohesive forces between molecules in the liquid, and an additionalamount of energy is requires to expand the liquid 1000+ percent (PΔD)into a resulting vapor phase (see FIG. 1A). Conversely, in thevapor-to-liquid transition, such energy will be released at the phasetransitions at the targeted tissue interface. That is, the heat ofvaporization is released in tissue when the media transitioning fromgaseous phase to liquid phase wherein the random, disordered motion ofmolecules in the vapor regain cohesion to convert to a liquid media.This release of energy (defined as the capacity for doing work) relatingto intermolecular attractive forces is transformed into therapeutic heatform thermotherapy within a targeted body structure. Heat flow and workare both ways of transferring energy.

In FIG. 1A, the simplified visualization of internal energy is usefulfor understanding phase transition phenomena that involve internalenergy transitions between liquid and vapor phases. If heat were addedat a constant rate in FIG. 1A (graphically represented as 5 calories/gmblocks) to elevate the temperature of water through its phase change toa vapor phase, the additional energy required to achieve the phasechange (latent heat of vaporization) is represented by the large numberof 110+ blocks of energy at 100° C. Still referring to FIG. 1A, it canbe easily understood that all other prior art ablation modalities—Rf,laser, microwave and ultrasound—create energy densities by simplyramping up calories/gm as indicated by the temperature range from 37° C.through 100° C. as in FIG. 1A. The prior art modalities make no use ofthe phenomenon of phase transition energies as depicted in FIG. 1A.

FIG. 1B graphically represents a block diagram relating to energydelivery aspects of the present invention. The system provides forinsulative containment of an initial primary energy-media within aninterior chamber of an instrument's working end. The initial, ascendantenergy-media interaction delivers energy sufficient to achieve the heatof vaporization of a selected liquid media such as saline within aninterior of the instrument body. This aspect of the technology requiresan inventive energy source and controller—since energy application fromthe source to the selected media (Rf, laser, microwave etc.) must bemodulated between very large energy densities to initially surpass thelatent heat of vaporization of the media within milliseconds, andpossible subsequent lesser energy densities for maintaining the media inits vapor phase. Additionally, the energy delivery system is coupled toa pressure control system for replenishing the selected liquid phasemedia at the required rate—and optionally for controlling propagationvelocity of the vapor phase media from the working end surface of theinstrument. In use, the method of the invention comprises the controlleddeposition of a large amount of energy—the heat of vaporization as inFIG. 1A—when the vapor-to-liquid phase transition is controlled at thevapor media-tissue interface. The vapor-to-liquid phase transitiondeposits about 580 cal/gram within the targeted tissue site to performthe thermal ablation.

The systems and probes of the invention are configured for controlledapplication of the head of vaporization of a vapor-to liquid phasetransition in an interface with tissue for tissue ablation, for thecreation of lesions in tissue or volumetric removal of tissue. Ingeneral, the instrument and method of the invention cause thermalablations rapidly and efficiently compared to conventional Rf energydelivery.

The instrument and method of the invention generate vapor phase mediathat is controllable as to volume and ejection pressure to provide anot-to-exceed temperature level that prevents desiccation, eschar, smokeand tissue sticking.

The instrument and method of the invention cause an energy-tissueinteraction that is imageable with intra-operative ultrasound or MRI.

The instrument and method of the invention cause thermal effects intissue that do not rely applying an electrical field across the tissueto be treated.

The instrument and method of the invention cause a liquid-to-vapor phasetransition in an interior chamber of the device that utilizes negativetemperature coefficient materials for modulating heating of salineinflows between (i) conducting heat to the saline media from aresistively heated component, and (ii) internal I²R heating of thesaline inflows.

In one embodiment, the instrument and method include means for applyingthe heat of ionization to a non-ionized flow media to create a plasma atthe working end for contacting tissue to thereby ablate the tissue.

Additional advantages of the invention will be apparent from thefollowing description, the accompanying drawings and the appendedclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a graphical depiction of the quantity of energy needed toachieve the heat of vaporization of water.

FIG. 1B is a diagram of phase change energy release that underlies onemethod of the invention.

FIG. 2A is a perspective view of the working end of an exemplary Type“A” probe of the present invention with an openable-closeable tissueengaging structure in a first open position.

FIG. 2B is a perspective view similar to FIG. 2A probe of the presentinvention in a second closed position.

FIG. 3 is a cut-away view of the working end of FIGS. 2A-2B.

FIG. 4 is a perspective view of the working end of FIG. 3 capturing anexemplary tissue volume.

FIGS. 5-6 are sectional schematic views of working end of FIG. 3depicting, in sequence, the steps of a method of the present inventionto seal or weld a targeted tissue volume, FIG. 5 illustrating thepressurized delivery of a liquid media to an interior channel, and FIG.6 depicting an electrical discharge that causes a liquid-to-gas phasechange as well as the ejection of the vapor media into the targetedtissue to thermally seal engaged tissue.

FIG. 7 is a Type “B” probe and system of present invention comprising ahandle with internal energy delivery mechanism for providing anon-ionized vapor and an elongate extension member configured as aflexible catheter.

FIG. 8A is an alternative probe similar to the embodiment of FIG. 7 withan extension member configured with a rigid needle-like working end.

FIG. 8B is an illustration of the needle-like working end of FIG. 8Adisposed in tissue showing a method of use in ablating a tumor.

FIG. 9A is an alternative probe similar to the embodiment of FIG. 7 withan extension member configured as a flexible catheter with at least onehollow shape-memory needle extendable therefrom.

FIG. 9B is an illustration of a method of using the extendable needle ofFIG. 9A to deliver energy to targeted tissue outside a body lumen suchas a fibroid or lung tumor.

FIG. 10 is a sectional view of the catheter sleeve of FIG. 7.

FIG. 11 is a cut-away view of the catheter handle of FIG. 7 depicting athermal energy delivery mechanism for the liquid-to-vapor conversion ofa pressurized inflow of a saline solution.

FIG. 12 is a cut-away view of an alternative system embodiment thatutilizes a negative temperature coefficient of resistance (NTCR)material for modulated energy delivery to inflowing media betweenconductive heating of the media and I²R heating of the media to causevaporization thereof.

FIG. 13 is an temperature resistance curve of the NTCR material of FIG.12.

FIG. 14A is an enlarged sectional view of the system of FIG. 12 showingoperational characteristics thereof.

FIG. 14B is an enlarged sectional view of a system similar to FIG. 12showing operational characteristics thereof.

FIG. 15 is a cut-away view of an alternative embodiment that utilizes aNTCR material for delivering the heat of vaporization to inflowingliquid media.

FIG. 16 is a cut-away view of an alternative embodiment for deliveringthe heat of vaporization to inflowing liquid media.

FIG. 17 is a cut-away view of an alternative embodiment for deliveringthe heat of vaporization to inflowing liquid media.

FIG. 18 is a cut-away view of an alternative embodiment for deliveringthe heat of vaporization to inflowing liquid media.

FIG. 19 is a cut-away view of an alternative embodiment for deliveringthe heat of vaporization to inflowing liquid media.

FIG. 20 is a cut-away view of an alternative embodiment for deliveringthe heat of vaporization to inflowing liquid media.

FIG. 21 is a cut-away view of a working end of as catheter sleeve thatis configured for delivering the heat of vaporization to inflowingliquid media.

FIG. 22 is as perspective view of another probe embodiment configuredfor tissue extraction.

FIG. 23 is an enlarged cut-away view of the working end of the probe ofFIG. 22.

FIG. 24A is an enlarged cut-away view of an alternative working endsimilar to the probe working end of FIG. 22.

FIG. 24B is an enlarged cut-away view of another working end similarsimilar to that of FIG. 22.

FIG. 25 is a cross-sectional view of the working end of FIG. 22.

FIG. 26 is an enlarged cut-away view of another working end that carriesat least one electrode for delivering energy to tissue or vapor mediaflows.

DETAILED DESCRIPTION OF THE INVENTION

1. Type “A” Thermotherapy Instrument.

Referring to FIGS. 2A, 2B and 3, the working end 10 of a “A” system 5 ofthe present invention is shown that is adapted for endoscopic proceduresin which a tissue volume T targeted for treatment (a thermoplasty) canbe captured by a loop structure. The working end 10 comprises a body 11of insulator material (see FIG. 3) coupled to the distal end ofintroducer member 12 extending along axis 15. In this exemplaryembodiment, the working end 10 has a generally cylindrical cross-sectionand is made of any suitable material such as plastic, ceramic, glass,metal or a combination thereof. The working end 10 is substantiallysmall in diameter (e.g., 2 mm to 5 mm) and in this embodiment is coupledto an elongate flexible introducer member 12 to cooperate with a workingchannel in an endoscope. Alternatively, the waking end 10 may be coupledto a rigid shall member having a suitable 1 mm to 5 mm or largerdiameter to cooperate with a trocar sleeve for use in endoscopic ormicrosurgical procedures. A proximal handle portion 14 of the instrumentindicated by the block diagram of FIG. 2A carries the various actuatormechanisms known in the art for actuating components of the instrument.

In FIGS. 2A, 2B and 3, it can be seen that the working end 10 carries anopenable and closeable structure for capturing tissue between a firsttissue-engaging surface 20A and a second tissue-engaging surface 20B. Inthis exemplary embodiment, the working end 10 and first tissue-engagingsurface 20A comprises at non-moving component indicated at 22A that isdefined by the exposed distal end of body 11 of working end 10. Thesecond tissue-engaging surface 20B is carried in a moving component thatcomprises a flexible loop structure indicated at 22B.

The second moving component or flexible loop 22B is actuatable by aslidable portion 24 a of the loop that extends through a slot 25 in theworking end to an actuator in the handle portion 14 as is known in theart (see FIG. 3). The other end 24 b of the loop structure 22B is fixedin body 11. While such an in-line (or axial) flexible slidable member ispreferred as the tissue-capturing mechanism for a small diameterflexible catheter-type instrument, it should be appreciated that anyopenable and closable jaw structure known in the art falls within thescope of the invention, including forms of paired jaws with cam-surfaceactuation or conventional pin-type hinges and actuator mechanisms. FIG.2A illustrates the first and second tissue-engaging surfaces 20A and 20Bin a first spaced apart or open position. FIG. 2B shows the first andsecond surfaces 20A and 20B moved toward a second closed position.

Now turning to the fluid-to-gas energy delivery means of the invention,referring to FIG. 3, it can be seen that the insulated or non-conductivebody 11 of working end 10 carries an interior chamber indicated at 30communicating with lumen 33 that are together adapted for delivery andtransient confinement of a fluid media M that flows into chamber 30. Thechamber 30 communicates via lumen 33 with a fluid media source 35 thatmay be remote from the device, or a fluid reservoir (coupled to a remotepressure source) carried within introducer 12 or carried within a handleportion 14. The term fluid or flowable media source 35 is defined toinclude a positive pressure inflow system which preferably is anysuitable high pressure pump means known in the art. The fluid deliverylumen 33 transitions to chamber 30 at proximal end portion 34 a thereof.The distal end portion 34 b of chamber 30 has a reduced cross-sectionthat functions to direct vapor media through a small outlet or nozzleindicated at 38.

Of particular interest, still referring to FIG. 3, paired spaced apartelectrode elements 40A and 40B are exposed in surface 42 of interiorfluid confinement chamber 30. In this exemplary embodiment, theelectrode elements 40A and 40B comprise circumferential exposed surfacesof a conductive material positioned at opposing proximal and distal endsof interior chamber 30, but other arrangements are possible. Theinvention can utilize any suitable configuration of spaced apartelectrodes (e.g., such as concentric electrode surfaces, intertwinedhelical electrode surfaces, adjustable spaced apart surfaces, or porouselectrodes) about at least one confinement chamber 30 or lumen portionof the system. Alternatively, each electrode can comprise one or moreprojecting elements that project into the chamber. The exemplaryembodiment of FIG. 3 shows an elongate chamber having an axial dimensionindicated at A and diameter or cross-section indicated at B. The axialdimension may range from about 0.1 mm to 20.0 mm and may be singular orplural as described below. The diameter B may range from microndimensions (e.g., 0.5 μm) for miniaturized instruments to a largerdimension (e.g., 5.0 mm) for larger instruments for causing thethermally induced liquid-to-vapor transformation required to enable thenovel phase change energy-tissue interaction of the invention. Theelectrodes are of any suitable material such as stainless steel,aluminum, nickel titanium platinum, gold, or copper. Each electrodesurface preferably has a toothed surface texture indicated at 43 thatincludes hatching, projecting elements or surface asperities for betterdelivering high energy densities in the fluid proximate to theelectrode. The electrical current to the working end 10 may be switchedon and off by a foot pedal or any other suitable means such as a switchin handle 14.

FIG. 3 further shows that a preferred shape is formed into thetissue-engaging surface 20A to better perform the method of fusingtissue. As can be seen in FIGS. 2B and 3, the first tissue-engagingsurface 20A is generally concave so as to be adapted to receive agreater tissue volume in the central portion of surface 20A. The secondtissue-engaging surface 20B is flexible and naturally will be concave inthe distal or opposite direction when tissue is engaged between surfaces20A and 20B. This preferred shape structure allows for controllablecompression of the thick targeted tissue volumes T centrally exposed tothe energy delivery means and helps prevent conductance of thermaleffects to collateral tissue regions CT (see FIG. 4) and as will bedescribed in greater detail below.

FIGS. 2A and 3 show that first tissue-engaging surface 20A defines anopen structure of at least one aperture or passageway indicated at 45that allows vapor to pass therethrough. The apertures 45 may have anycross-sectional shape and linear or angular route through surface 20Awith a sectional dimension C in this embodiment ranging upwards frommicron dimensions (e.g., 0.5 μm) to about 2.0 mm in a large surface 20A.The exemplary embodiment of FIG. 3 has an expanding cross-sectiontransition chamber 47 proximate to the aperture grid that transitionsbetween the distal end 34 b of chamber 30 and the apertures 45. However,it should be appreciated that such a transition chamber 47 is optionaland the terminal portion of chamber 30 may directly exit into aplurality of passageways that each communicate with an aperture 45 inthe grid of the first engaging surface 20A. In a preferred embodiment,the second tissue-engaging surface 20B defines (optionally) a grid ofapertures indicated at 50 that pass through the loop 22B. Theseapertures 50 may be any suitable dimension (cf. apertures 45) and areadapted to generally oppose the first tissue-engaging surface 20A whenthe surfaces 20A and 20B are in the second closed position, as shown inFIG. 2B.

The electrodes 40A and 40B of working end 10 have opposing polaritiesand are coupled to Rf generator or electrical source 55. FIG. 3 showscurrent-carrying wire leads 58 a and 58 b that are coupled to electrodes40A and 40B and extend to electrical source 55 and controller 60. In apreferred embodiment of the invention, either tissue-engaging surfaceoptionally includes a sensor 62 (or sensor array) that is in contactwith the targeted tissue surface (see FIG. 2A). Such a sensor, forexample a thermocouple known in the art, can measure temperature at thesurface of the captured tissue. The sensor is coupled to controller 60by a lead (not shown) and can be used to modulate or terminate powerdelivery as will be described neat in the method of the invention.

Operation and use of the working end of FIGS. 2A, 2B and 3 in performinga method of treating tissue can be briefly described as follows, forexample in an endoscopic polyp removal procedure. As can be understoodfrom FIG. 4, the working end 10 is carried by an elongate catheter-typemember 12 that is introduced through a working channel 70 of anendoscope 72 to a working space. In this case, the tissue T targeted forsealing is a medial portion 78 of as polyp 80 in a colon 82. It can beeasily understood that the slidable movement of the loop member 22B cancapture the polyp 80 in the device as shown in FIG. 4 after beinglassoed. The objective of the tissue treatment is to seal the medialportion of the polyp with the inventive thermotherapy. Thereafter,utilize a separate cutting instrument is used to cut through the sealedportion, and the excised polyp is retrieved for biopsy purposes.

Now turning to FIGS. 5 and 6, two sequential schematic views of theworking end engaging tissue T are provided to illustrate theenergy-tissue interaction caused by the method of the invention. FIG. 5depicts an initial step of the method wherein the operator sends asignal to the controller 60 to delivery fluid media M (e.g., salinesolution or sterile water) through lumen 33 into chamber 30. FIG. 6depicts the next step of the method wherein the controller delivers anintense discharge of electrical energy to the paired electrode elements40A and 40B within chamber 30 indicated by electric field EF. Theelectrical discharge provides energy exceeding the heat of vaporizationof the contained fluid volume. The explosive vaporization of fluid mediaM (of FIG. 5) into a vapor or gas media is indicated at M′ in FIG. 6.The greatly increased volume of gas media M′ results in the gas ejectedfrom chamber 30 at high velocity through apertures 45 of surface 20Ainto the targeted tissue T. The liquid-to-vapor transition caused by theelectrical discharge results in the vapor media M′ having a temperatureof 100° C. or more as well as carrying the heat of vaporization todeliver thermal effects into or through the targeted tissue T, asindicated graphically by the shaded regions of gas flow in FIG. 6. Thefluid source and its pressure mechanism can provide any desired level ofvapor ejection pressure. Depending on the character of the introducedliquid media, the media is altered from a first lesser temperature to asecond greater temperature in the range of 100° C. or higher dependingon pressure. The ejection of non-ionized vapor media M′ and itscondensation will uniformly and very rapidly elevate the temperature ofthe engaged tissue to the desired range of about 65° C. to 100° C. tocause hydrothermal denaturation of proteins in the tissue, and to causeoptimal fluid inter-mixing of tissue constituents that will result in aneffective seal. In effect, the vapor-to-liquid phase transition of theejected media M′ will deposit heat equal to the heat of vaporization(also sometimes called the heat of condensation) in the tissue. At thesame time as the heat of vaporization of vapor media M′ is absorbed bywater in the targeted tissue, the media converts back to a liquid thushydrating the targeted tissue T. Such protein denaturation byhydrothermal effects differentiates this method of tissue sealing orfusion from all other forms of energy delivery, such as radiofrequencyenergy delivery. All other forms of energy delivery vaporize intra- andextracellular fluids and cause tissue desiccation, dehydration orcharring which is undesirable for the intermixing of denatured tissueconstituents into a proteinaceous amalgam.

The above electrical energy deliver step is continuous or can berepeated at a high repetition rate to cause a pulsed form of thermalenergy delivery in the engaged tissue. The fluid media M inflow may becontinuous or pulsed to substantially fill chamber 30 before anelectrical discharge is caused therein. The repetition rate ofelectrical discharges may be from about 1 Hz to 1000 Hz. Morepreferably, the repetition rate is from about 10 Hz to 200 Hz. Theselected repetition rate preferably provides an interval betweenelectrical discharges that allows for thermal relaxation of tissue, thatmay range from about 10 ms to 500 ms. The electrical source or voltagesource 55 may provide a voltage ranging between about 20 volts and10,000 volts to cause instant vaporization of the volume of fluid mediaM captured between the electrode elements 40A and 40B. After a selectedtime interval of such energy application to tissue T, that may rangefrom about 1 second to 30 seconds, and preferably from about 5 to 20seconds, the engaged tissue will be contain a core region in which thetissue constituents are denatured and intermixed under relatively highcompression between surfaces 20A and 20B. Upon disengagement and coolingof the targeted tissue T, the treated tissue will be fused or welded.Over time, the body's wound healing response will reconstitute thetreated tissue by means of fibrosis to create a collagenous volume orscar-like tissue.

2. Type “B” Thermotherapy Instrument.

Now referring to FIGS. 7-11, other embodiments of medical probes andvapor generation and delivery systems are shown. In the previousembodiment, the working end was optimized for engaging and sealingtissue with a working surface that is configured for clamped contactwith tissue. In the embodiments of FIGS. 7-11, the probes and workingends are adapted for controlled application of energy by means of avapor-to-liquid phase change energy release in an endoluminalapplication or in an interstitial application of energy.

In FIG. 7, it can be seen that probe system 200A includes a handleportion 202 that transitions into an elongated extension member 205. Inthe embodiment of FIG. 7, the extension member 205 comprises a flexiblecatheter sleeve that is configured for introduction through a body lumenor cavity such as a blood vessel, a patient's airways, a sinus, auterus, a fallopian tube or the like. The diameter of extension member205 can range from about 1 Fr. to 6 Fr. or more. The fluid inflowsource, energy delivery source and optional negative pressure source areoperatively connected to handle portion 202 and are further describedbelow.

In FIG. 8A, the probe system 200B consists of handle portion 202 thattransitions into elongated extension member 205 that is substantiallyrigid and has a sharp hollow needle tip 206 for penetrating into tissue.FIG. 8B illustrates the needle tip 206 having a plurality of vapor portsor outlets 207 therein for the interstitial introduction of vapor. Inone embodiment as in FIG. 8B, the probe 200B with a rigid needle-likeworking end can be configured with a cross-section and length suited forablating a tumor in a liver, breast, lung, kidney, prostate, uterinewall or the like in an open or endoscopic approach. The fluid inflowsource and energy delivery source are provided in handle portion 202 andare described in more detail below. In the probe embodiment 200B ofFIGS. 8A-8B, the working end 206 also can comprise at least oneelectrode 208 for delivering high frequency energy to the tissue and/orthe nor-ionized vapor media being introduced into targeted tissue T suchas a tumor via the outlets 207 in the needle tip. FIGS. 8A-8B illustratean electrode 208 in the needle tip cooperating with a ground pad 209.

FIG. 9A-9B illustrate another the probe and system 200C that consists ofhandle portion 202 that transitions into an elongated member 205 thatcomprises a flexible catheter sleeve as in FIG. 7 with a working end 210that carries at least one extendable-retractable hollow needle 211 fordelivering vapor to treat tissue. The flexible elongated member 205 thuscan be navigated through a body lumen and then the at least one needle211 with vapor outlets 207 can be penetrated into tissue from theworking, end as shown in FIG. 9B. The at least one needle 211 can beactuated by means of art actuator 213 in handle portion 202. Anembodiment as in FIGS. 9A-9B can be configured with a cross-section andlength for treating abnormal prostate tissue, abnormal uterine walltissue, abnormal lung tissue, abnormal bladder tissue, abnormalgastrointestinal tract tissue and the like indicated at T. The workingend 210 can further carry at least one balloon for stabilizing theworking end in a body lumen or expanding in a body cavity to correctlylocalize the needle(s). The working end 210 can further carry anultrasound transducer for imaging the treatment. The working end 210 canfurther include an aspiration channel coupled to a negative pressuresource 270 for suctioning the lumen wall against the working end.

In preferred embodiments of extension member 205 that comprise flexibleendoluminal catheters, the member is fabricated of a single polymericmaterial or a combination of polymer layers 224 a and 224 b (FIG. 10).The exterior layer can have reinforcing in the form of braiding as isknown in the art. In the embodiment of FIG. 10, the interior layer 224 ais of a material having a low thermal conductivity, for example lessthan about 1.0 W/m-K, and preferably less than about 0.50 W/m-K. In oneexample, an unreinforced polyetheretherketone (PEEK) has a thermalconductivity of about 0.25 W/m-K and can be used for at least innerlayer 224 a of the extension member 205 FIG. 10). PEEK is hightemperature resistant engineered thermoplastic with excellent chemicaland fatigue resistance plus thermal stability. PEEK had a maximumcontinuous working temperature of 480° F. and retains its mechanicalproperties up to 570° F. in high-pressure environments. Other materialsused in the extension member can comprise formulations or blends ofpolymers that include, but are not limited to PTFE, polyethyleneterephthalate (PET), or PEBAX. PTFE (polytetrafluoroethylene) is afluoropolymer which has high thermal stability (up to 260° C.), ischemically inert, has a very low dielectric constant, a very low surfacefriction and is inherently flame retardant. A range of homo andco-fluoropolymers are commercialized under such names as Teflon®,Tefzel®, Neoflon®, Polyflon® and Hyflon®. In another embodiment, theextension member or catheter 205 can carry another layer or structure224 e of any suitable thickness intermediate the inner and outer layers224 a and 224 b that comprises a low thermal conductivity layer. Such alayer can comprise an air gap, insulative ceramic or glass microspheresor fibers, or at least one lumen that carries a cryofluid incommunication with a cryogenic fluid source as in known in the art (seeFIG. 10).

Now turning to FIG. 11, the cut-away view of the handle portion 202 ofany of the embodiments of FIGS. 7-9B is shown. The handle 202 has aninterior chamber 225 formed within the interior of an insulator materialindicated at 228 such as a ceramic or a combination of materials toinsulate the interior chamber 225 from the surface of the handle. Aninflow channel 230 communicates with pressurized inflow source 240 offluid or liquid media via flexible tube 242 coupled to fitting 244. Acomputer controller 245 is provided to control parameters of fluidinflows to interior chamber 225. The interior chamber 225 has a distalregion in which media flows transition to outflow channel 212 thatextends to a flexible or rigid extension member 205 and to an exemplaryworking end indicated at 215. In FIG. 11, it can be seen that Rf source250 (also operatively connected to controller 245) has first polarity(+) lead 252 a and opposing second polarity (−) lead 252 b that arecoupled respectively to first and second conductive surfaces orelectrodes 255A and 255B exposed in interior chamber 225 that serve as athermal energy delivery mechanism. The first conductive surface 255A isan inner or outer surface of elongated diffuser structure 256 having aninterior bore 258 therein. Thus, the diffuser structure 256 defines aplurality of diffuser apertures or ports 260 in the wall of thestructure for diffusing the flow of pressurized liquid media M into theinterior chamber 225. The diffuser apertures or ports 260 have asuitable dimension and configuration for diffusing or atomizing a highpressure inflow of flow media M from source 240, which preferably is asaline solution. The second polarity (−) lead is coupled to conductivesurface 255B which comprises a radially outward surface of interiorchamber 225. In the embodiment shown in FIG. 11, it can be seen that thefirst and second conductive surfaces 255A and 255B are concentric,extend over a substantial length of the handle and have a large surfacearea with a fixed spaced apart radial dimension indicated at 262. In oneembodiment, the radial dimension 262 between the electrode surfaces isselected to match the particular impedance and other operatingcharacteristics of the Rf generator.

Referring to FIG. 11, in a method of operation, the system injects avolume of a conductive liquid such as hypertonic saline flow media M ata selected rate under pressure from source 240 which is diffused andatomized by ports 260 as the media enters interior chamber 225.Contemporaneous with injection and diffusion of the flow media, thesystem delivers sufficient current from source 250 and controller 245 tothe conductive atomized saline via the opposing polarity surfaces 255Aand 250B which instantly vaporizes the water in the flow media M togenerate a non-ionized vapor M′ that is injected from interior chamber225 into lumen or channel 212 of the elongated extension member 205. Theinstantaneous Increase in volume of media in the liquid-to-vapor phasetransition greatly increases interior pressures in interior chamber 225to thereby accelerate the flow into and through the extension member 205to a least one open termination in the distal end of the member 205. Asshown in FIG. 11, the system and handle can include an optional pressurerelief valve schematically indicated at 264 so that any overpressures inthe interior chamber are released. The release of any overpressure canbe vented through an additional lumen in the supply tube 242 or toanother chamber in the handle 202.

Referring to FIGS. 7, 8A and 9A, the system optionally includes anegative pressure source 270 that communicates with another lumen 273 incatheter sleeve 205 that has an open distal termination in the workingend 215 of the extension member 205. The handle 202 further has asuitable channel indicated at 276 that extends between the negativepressure source 270 and aspiration lumen 273 in extension member 205.

Now turning to FIG. 12, another system embodiment 400A is shown whereinan interior chamber 410 again in disposed in a handle portion 412 of theinstrument that includes opposing polarity conductive components 415Aand 415B that function as the thermal energy delivery mechanism. Itshould be appreciated that the components of the system can also bereduced in scale to be positioned in an elongated extension member 205as in FIGS. 7, 8A and 8B. In the system embodiment of FIG. 12 andrelated versions that follow in FIGS. 13-21, the systems include the useof temperature coefficient materials for optimizing energy delivery to aconductive flow media (such as saline solution) from a radiofrequency(Rf) source 420. The working end 422 of the system is shownschematically and includes an elongate member 424 with at least onelumen 425 for carrying vapor media to exit a working end surface forinterfacing with targeted tissues or body structure, including but notlimited to (i) a needle for penetrating soil tissue, (ii) a blunt-tippedprobe for painting across a tissue surface or interior body surface suchas joint tissue; (iii) a punch or threaded tip for penetrating into hardtissue such as bone to treat a tumor, avascular necrosis or the like;(iv) an elongate flexible probe or catheter device for endoluminalenergy delivery; (v) a balloon, a flexible film or expandable surfacefor engaging body structure, (vi) any jaw structure or approximatingcomponents for capturing tissue; or (vii) any blade edge, cutting loopor rotatable element for cutting tissue.

In FIG. 12, the handle 412 is fabricated with an insulator materialindicated at 428 that surrounds interior chamber 410. An inflow channel430 communicates with the inflow source 435A of fluid media M andpressure control system 435B via flexible tube 436 coupled to fitting438. The interior chamber 410 has a distal region in which media flowstransition to outflow channel 425 that extends to the working end 422.In FIG. 12, it can be seen that the first polarity (+) lead is coupledto a closed end elongated diffuser structure 440 of which at least aportion comprises the first conductor 415A. The diffuser structure 440has diffuser ports 444 about and along its length that have a suitabledimension and configuration for diffusing or atomizing a high pressureinflow of saline media M into small cross-section flows. The secondpolarity (−) lead is coupled to conductive sleeve 445, the surface ofwhich comprises the second polarity conductor 415B about the radiallyoutward surface of interior chamber 410. Of particular interest, theinterior chamber 410 is occupied in part by a flow permeable structure450 that has negative temperature coefficient of resistance (NTCR)properties—and in this case comprises packed together porous siliconcarbide microspheres indicated at 455. Such NTCR flow permeablestructures 450 in the form of assembled porous elements, porous ornon-porous rods, tubes, sleeves and the like are available fromSaint-Gobain Ceramics, 23 Acheson Drive, Niagara Falls, N.Y. 14303 USA.The NTCR properties of an exemplary silicon carbide are shown in FIG.13, wherein the resistivity in ohms-cm rapidly decreases by orders ofmagnitude in a selected temperature range between about 100° C. and 600°C. Further, the NTCR flow permeable structure 450 is spaced apart fromstructure 440 and first polarity conductor surface 415A by a space or bynon-conductive ceramic or glass microspheres 460 as depicted in FIG. 12.Suitable non-conductive spheres are available from Saint-GobainCeramics, 23 Acheson Drive, Niagara Falls, N.Y. 14303 USA or under thetrade name SPHERIGLASS® from Potters Industries, Inc. P.O. Box 840,Valley Forge, Pa. 19482-0840. The NTCR structures can be fabricated fromvarious materials besides silicon carbide, such as tungsten carbide,boron carbide, boron nitride, zirconia or combinations or assembliesthereof, or doped germanium or silicon glass composites. The flowpermeable structure 450 alternatively cart comprise structures, elementsor assemblies of a non-conductive glass or ceramic that is coated withany suitable NTCR material.

Still referring to FIG. 12, in a method of operation, the system injectsliquid saline media under pressure from source 435A which is diffused bythe atomization ports 444 in the diffuser structure. The high pressureflow of diffused saline is then within the reduced cross-section openpathways of the flow permeable structure 450. Contemporaneous withinjection and diffusion of the saline, the system delivers sufficient Rfcurrent from source 420 to the conductive atomized saline via theopposing polarity surface conductors 415A and 415B to instantly elevateH₂O in the media to cause a liquid-to-vapor phase change therein (viaI²R or Joule heating). The instantaneous increase in volume of the vaporphase media greatly increases interior pressures to thereby acceleratethe media flow in the distal direction in and about the flow permeablestructure 450 through outflow channel 425. The system includes anoptional pressure relief valve schematically indicated at 458 in FIG.12. The system also can include a check valve (not shown) in inflowchannel 430 for preventing backflows when the system is turned on andoff.

Of particular interest, during operation of the system, the Rf currentflow in the interior chamber 410 and flow permeable structure 450 ofFIG. 12 will seek a path of least resistance between the opposingpolarity surface conductors 415A and 415B, which is shown in an enlargedschematic views in FIGS. 14A and 14B as dashed lines of current paths170. An initial intense application of Rf energy will initially causeohmic heating (I²R or Joule heating) and vaporization of the atomizedsaline within the flow permeable structure 450—with the arc of currenteffectively flowing from the surface coil doctors 415A and 415B asindicated in FIG. 14A.

Referring now to FIG. 14B, at the same time that the saline is vaporized(as in FIG. 14A), the vapor media will elevate the temperature of theNTCR flow permeable structure 450 thus reducing its resistivity to causesome current flow therein. The regions of the NTCR structure from whichthe current couples with the conductive fluid will have the highestinstantaneous temperature and hence lowest resistance. The operation ofthe system thus cause a reduced resistivity region so that current paths170 are allowed to adjust in length dynamically. It is believed that theresult will be that current path lengths will self-adjust optimally tothe particular output, waveform and operating characteristics of the Rfgenerator used to deliver energy to the system. As depicted in FIG. 14B,a particular Rf generator will delivery power optimally to the atomizedmedia across a certain dimension D, for example between points 415A and415B—assuming certain other operating parameters such as atomized salineinflow rates and volumes, interior pressures determined by permittedoutflow rates, and the specified resistivity of the saline media.Another particular Rf generator would deliver power optimally across adifferent dimension between opposing polarity surface, for example D′and surface region 480′. Preferably, the interior chamber dimensions canbe designed to match the computed optimal operating, characteristics andimpedance of a particular generator, such as dimension D in FIG. 14B.The improved system of the invention uses NTCR surfaces or an NTCR flowpermeable structure 450 as in FIGS. 12, 14A and 14B that has selectedresistivity-temperature characteristics, wherein the NTCR surfaces willeffectively self-adjust the average dimension between spaced apartsurface portions or regions (e.g., 415A and 480-480′) that apply energyto the inflowing saline media during operation of the system. Thus, theNTCR surfaces can self-adjust the average dimension between spaced apartsurface portions, for 415A and 480′ in FIG. 14B when the vapor phasemedia's resistance is lowered, the flow velocity is increased or whenother such operation parameters are changed by external controls or byRf energy delivery and Joule heating itself. Further, the NTCR surfaceswill allow for different “radial” dimensions between the effectiveopposing polarity conductor surfaces over an axial length of theinterior chamber 410 during operation as schematically indicated by line480″ in FIG. 14B. Still further, the NTCR surfaces will resistively heatand thereby deliver heat to the atomized saline by means of conductionin addition to Joule heating to enhance energy delivery for theliquid-to-vapor conversion in chamber 410.

FIG. 15 illustrates an alternative embodiment of system 400B wherein theopposing polarity leads are coupled to axially spaced apart conductivesurfaces 415A and 415B, rather than the radially spaced apart surfacesin the embodiment of FIGS. 12 and 14A-14B. In FIG. 15, it can be seenthat the saline media M is introduced into the interior chamber 410through closed end sleeve 440 and atomized by diffuser ports 444. Inthis embodiment, the interior chamber 410 has first, and second NTCRflow permeable structures 450 and 450′—which again can be packedtogether porous silicon carbide microspheres indicated at 455. The NTCRstructures 450 and 450′ are spaced apart by a flow permeableelectrically insulative material such as ceramic microspheres 460. Inthis embodiment, the NTCR structure can be designed for rapid internalresistive heating. In use, inflowing atomized liquid that reaches thefluid permeable region around the insulative microspheres 460 will thenbe instantly vaporized by a combination of I²R heating of the resistivesaline components (current paths 470) and the conduction of heat fromthe very high surface area of the internally heated NTCR structure tothe media. The system of FIG. 15 thus has two NTCR flow permeablestructures 450 and 450′ that can self-adjust the average dimensionbetween the spaced apart surface portions, for example D and D′, thatapply Rf energy to the inflowing media M during operation of the system.This system again can self-adjust the changing resistivity of the vaporphase media as it propagates distally at high velocity, and otheroperation parameters such as the pressure and volumes of media inflowsper unit time. Thus, the liquid-to-vapor conversion in chamber 410 willoccur dynamically over a range of interior regions of the device duringoperation. It should be appreciated that the NTCR structures also can bedesigned to have a gradient in NTCR properties (i.e.,temperature-resistance curves as in FIG. 13) between the opposingpolarity surfaces 415A and 415B to induce current arcing through theinflow media M about selected geometries with operational arcinggeometries changing during operation.

FIG. 16 illustrates another system embodiment 400C wherein the opposingpolarity leads are coupled to radially spaced apart conductive surfaces415A and 415B that couple to the fluid permeable diffuser structuressuch as a syntactic material or open-cell material. The terms“syntactic”, “open-cell” and “flow-permeable” as used herein refer toany structure that has substantial porosity for allowing fluid flowtherethrough. Such materials have the advantage of providing very highsurface areas (i) for conducting heat from an I²R heated material topressurized media flows therein, or (ii) for conducting Rf current intoa conductive media to cause I²R heating and vaporization of the media.The open-cell material can be a foam, sintered material, a platedentangled filament material, a microchannel structure or any ordered ordisordered structure with flow passageways therein. For example,syntactic metals and ceramics are available from ERG Materials andAerospace Corp., 900 Stanford Avenue, Oakland, Calif. 94608 and PocoGraphite (http://www.poco.com).

In the embodiment of FIG. 16, at least one and preferably both of thesyntactic structures have NTCR surfaces 450 and 450′ or are fabricatedof an NTCR material. The syntactic structure is further selected toprovide an internal pore dimension that causes diffusion and smallcross-section flows of the saline media M as it is introduced intointerior chamber 410 through channel 430 to thus function as thediffuser ports 444 in previous embodiments (see FIG. 12).

Of particular interest, the NTCR materials of the embodiment of FIG. 16will cause current flows into and across the following conductive mediato cause I²R heating and vaporization thereof—and during operation themean dimension of the current path can transition from path 470(dimension D) to path 470′ (dimension D′) as the impedance and velocityof the media changes. It is believed that the NTCR structures will causecurrent to jump preferentially from a particular location on thestructure into the media based on the operating parameters of the Rfgenerator to cause a current path of a selected length, which in turnwill cause very high heating of the particular location of the NTCRmaterial which will further cause the resistance of the material tolower at the particular location. During operation, as the velocity andimpedance of the liquid-to-vapor converting media changes, theparticular location(s) on the NTCR structure that current jumps to orfrom can transition both radially and axially to match the operatingparameters of the Rf generator.

FIG. 17 illustrates another system embodiment 400D wherein the opposingpolarity leads and conductive surfaces 415A and 415B are spaced apartaxially and are coupled to syntactic structures having NTCR surfaces 450and 450′ or wherein the structures are fabricated of an NTCR material.The system of FIG. 17 will operate based on the principles describedabove with reference to FIG. 17. During operation, as the changingvelocity and impedance of the liquid-to-vapor conversion is ongoing, theNTCR structures can self-adjust the axial dimension of the jump of Rfcurrent to match the operating parameters of the Rf generator. Inanother similar embodiment, the syntactic structures can be fabricatedof a positive temperature coefficient of resistance (PTCR) ceramic orother material, which will conduct current to a conductive flow mediawith the conductive surface portions of the material changing duringoperation. Thus, the NTCR material delivers thermal energy to inflowingby conduction and then by Rf ohmic heating of the liquid wherein a PTCRmaterial delivers energy to the inflowing liquid initially by ohmicheating of the liquid and subsequently by conduction from the PTCRmaterial to the liquid.

FIG. 18 illustrates another system embodiment 400F wherein the opposingpolarity leads and conductive surfaces 415A and 415B are spaced apartradially. In this embodiment, rather than providing a syntacticstructure with larger surface areas, a central structure 482 is providedthat has fins, projections or other such elements indicated at 485 forproviding substantially high surface areas and for providing surfacesthat provide for varied dimension current paths to thus operate on theprinciples described above with reference to FIG. 17. The tins 485 haveNTCR surfaces 450 as described above and again the structure providesdiffusion ports 444 for atomizing saline inflows. The tins or projectingelements 485 can have any suitable configuration and dimension such asradial elements, helical elements, axial elements or a combinationthereof and can extend from either or both the surface of the chamber410 or from a central member 482 in the chamber.

FIG. 19 illustrates another system embodiment 400F which operates as theembodiments of FIGS. 17 and 18 except the conductive surface 415B istapered to provide a wider range of radial dimensions extending axiallyover the length of the interior chamber.

FIG. 20 illustrates another system embodiment 400G which operates as theembodiments of FIGS. 17-19 except the conductive surfaces are carried bya plurality of assembled or packed together linear filaments 488 whichcan be tapered or flexible as in wire elements. Gaps between theelements 488 provide diffusion ports 444 thus providing a diffuserstructure as described previously.

FIG. 21 illustrates another system embodiment 500 which includescomponents and features as in the embodiments of FIGS. 12-20 except thatthe configuration is adapted for the working end of a small diameterrigid probe or a flexible catheter, in FIG. 21, the interior chamber 510comprises an elongate lumen of a member 512 having an insulated wall514. A flow diffuser is located in a proximal portion of lumen 510 (notshown). In one embodiment, the interior of the lumen 510 comprises anNTCR surface indicated at 515. The NTCR surface 515 is coupled toinsulated lead 518 and the Rf source 420 to thus comprise a seriescircuit. NTCR surface 515 is capable of internal I²R heating to therebycause heating and vaporization of media flows in the lumen. A conductivefilament 520 is carried in lumen 510 with the filament having kinks orbends 522 so that the filament does not continuously contact the NTCRsurface. The filament 520 is electrically conductive and is coupled tothe Rf source to provide a parallel circuit when Rf current jumps fromsurface 515 to the filament 520 through the conductive media whichthereby vaporizes the media. In operation, the NTCR surface 515 willtend to cause current flow into the filament 520 at contact points 524but inflowing media M will cool that location inducing the current toflow into the media and thereby vaporize the media. A plurality of suchfilaments 520 can be carried in a microchannel structure as describedabove—with a single filament in each microchannels. In anotherembodiment, the filament 920 also can have an NTCR surface.

In another embodiment similar to FIG. 21, the interior surface of lumen510 and/or the filament can comprise a positive temperature coefficientof resistance (PTCR) material. In operation, the PTCR materials wouldnot internally heat but would be adapted to only cause I²R heating ofthe fluid media M itself within the lumen for causing theliquid-to-vapor conversion.

FIG. 22-24 illustrate another probe embodiment 600 that is adapted fortissue ablation, tissue disintegration and tissue extraction. The probehas a handle portion and vapor source that is similar to any of thehandle embodiments of FIGS. 7, 11, 12, and 14-20 for providing a flow ofa vapor media. Probe 600 of FIG. 22 has electrical source 420, fluidinflow source 435A and controller 435B as described with reference toFIGS. 12 and 14-20. Probe 600 also has a negative pressure source 270 asdescribed generally with reference to FIGS. 7 and 11 above.

The probe 600 of FIG. 22 has handle portion 602 that transitions toextension member 605 having axis 608 that extends to working end 610.The probe 600 has a central aspiration lumen 615 extending through theprobe body to an open distal termination. The probe has a vapor flowchannel 620 for providing a flow of vapor to working end 610 that isconfigured as a concentric channel between first and second walls, 622and 624 respectively, surrounding the aspiration channel 615 (FIGS.22-23). In one embodiment, the extension member 605 is configured as aliposuction probe and ranges in diameter from about 1 mm to 10 mm. Inanother embodiment, extension member 605 is configured for extraction ofintervertebral disc material and ranges in diameter from about 1 mm to 5mm. As can be seen in FIG. 23, the outlets 625 for introducing the vaporinto an interface with tissue are disposed in the distal terminationregion 626 of aspiration lumen 615. The outlets 625 in FIG. 23 are shownas round ports hut also can be elongated and/or arcuate as shown inFIGS. 24A and 24B. As can be seen in FIG. 23, the outlets 625 arepositioned distance D from the distalmost surface 628 of the extensionmember 605 which can range from about 0.1 mm to 5 mm inward of surface628. The number of outlets 625 can range from about 2 to 20 and can haveany suitable cross-section to fit in a particular dimension ofaspiration channel 615. Of particular interest, referring to FIG. 23,the axis 630 of each outlet 625 that extends through inner wall 624 ofthe extension member is angled proximally to thereby eject vapor mediamore in line with the flow direction induced by aspiration forces. Inanother embodiment as shown in FIG. 25, the axis 630 of each outlet 625extending through inner wall 624 of extension member 605 also in angledradially rather than being directed toward the axis of extension member605. The radial angle of outlet 625 as shown in FIG. 25 provides flowsthat create a vortex in combination with the aspiration forces.

In use, the probe 600 and system of FIGS. 22-25 can be used to extractsoft tissue from the interior of a patient's body such as in aliposuction procedure. The aspiration forces suction soft tissue intodie distal termination region 626 of aspiration lumen 615 wherein thehigh velocity injection of vapor media, which can be provided underpressure ranging from about 10 psi to 1,000 psi, will apply thermalenergy in the vapor-to-liquid phase transition as well as somemechanical energy to thermally weaken and dissociate covalent bonds anddissolve and disintegrate the soft tissue. The continued aspirationforces then extract the tissue from the treatment site through channel615. The method of the invention includes using the energy levelsassociated with the vapor injection to discriminate the type of tissuebeing disintegrated and extracted. For example, in removing a discnucleus, the softer tissue of the nucleus can be extracted at selectedvapor delivery parameters wherein the same parameters will not ablateand disintegrate adjacent annulus tissue. In another embodiment, theconcentric flow channel 620 can carry at least one diffuser structureand/or NTCR structure with opposing polarity electrodes for vaporizingthe liquid flow media rather than generating the vapor in the handleportion of the probe.

In another embodiment in FIG. 26, a distal region 640 (and optionallyother more proximal regions) of the aspiration channel 615 carry atleast one electrode coupled to an electrical source 420 that is adaptedto deliver sufficient voltage to the vapor and/or tissue in channel tofurther ablate the tissue. The embodiment of FIG. 26 includes concentricfirst polarity electrode 645A and second polarity electrode 645B thatare axially spaced apart, but the electrodes also can be spaced aparthelically, radially or any combination thereof. One of the electrodescan disposed in inflow channel 620 proximal to the flow outlets 625 asshown in FIG. 26, or both electrodes 645A and 645B can be in aspirationchannel 615. The extension member 605 is fabricated of an insulativematerial or coated with an insulator to maintain electrical isolationbetween the electrodes as is known in the art. In one embodiment, theelectrical source 420 is configured for applying sufficient voltage tonon-ionized vapor media as it exits outlets 625 to provide the heat ofionization to convert the vapor to an ionized media or plasma forablating tissue. Thus, the probe has a first or proximal energy deliversystem for delivering the heat of vaporization and a second distalsystem for delivering the heat of ionization. The plasma then can becreated in intervals or on-demand to disintegrate tissue.

Although particular embodiments of the present invention have beendescribed above in detail, it will be understood that this descriptionis merely for purposes of illustration and the above description of theinvention is not exhaustive. Specific features of the invention areshown in some drawings and not in others, and this is for convenienceonly and any feature may be combined with another in accordance with theinvention. A number of variations and alternatives will be apparent toone having ordinary skills the art. Such alternatives and variations areintended to be included within the scope of the claims. Particularfeatures that are presented in dependent claims can be combined and fallwithin the scope of the invention. The invention also encompassesembodiments as if dependent claims were alternatively written in amultiple dependent claim format with reference to other independentclaims.

What is claimed is:
 1. A method for delivering energy to mammalian bodystructure, comprising: providing an elongated probe with a proximal endand a working end; providing a flow of a non-ionized flow media from atleast one port in the working end, wherein a source of the non-ionizedflow media is positioned remotely from the working end; and controllingejection of the non-ionized flow media from the working end, wherein thenon-ionized flow media carries sufficient thermal energy such thatcontact of the non-ionized flow media with mammalian body structurecauses modification of the body structure through a phase change of thenon-ionized flow media.
 2. The method of claim 1 including providing theflow of non-ionized flow media from a needle-like working end into thebody structure.
 3. The method of claim 1 including providing the flow ofnon-ionized flow media from the working end into at least one of a bodylumen, soft tissue, surface tissue and bone.
 4. The method of claim 1including providing the flow of non-ionized flow media in at least oneof as distal direction relative to as probe axis, a proximal directionrelative the said axis and substantially perpendicular to said axis. 5.The method of claim 4 including providing the flow of non-ionized flowmedia from at least one proximally-oriented port into said interiorchannel in the probe.
 6. The method of claim 5 including providingnegative pressure aspiration forces to said interior channel in theprobe.
 7. The method of claim 1 wherein the source of the non-ionizedflow media is positioned at least 5 mm; 10 mm and 100 mm from a surfaceof the working end.